What Am I Doing Wrong?! (Or Not Doing..)

Twice I have had to make black fondant and both times it has fallen apart!

The first time, before I found CC, I never thought to make it brown first, so I made regular MMF, and put LOADS of black gel paste - when I went to roll it out, it just kept crumbling. I ended up having to put it on the cake WAY too thick, because I couldn't get it anywhere near thin, and I had to cover an inch of the bottom of the cake in icing, because the fondant was so crumbled and in pieces that it didn't cover all the way down the sides of the cake!

The second time, I added cocoa in, and then added the black gel paste. I had needed brown too, so I kept some of the MMF with just cocoa aside and it was fine (I was moulding things out of it). But when I had to mould the black MMF, it was the same problem, and I couldn't get it smooth and I had to use piping gel to hold it together after I moulded what I could out of it.

I think adding the coco powder makes it too dry but then the added gel color should help with that. But I remember reading to make chocolate fondant with chocolate melts and then color it from there. I never use the chocolate because we can't. Once I had a batch that wanted to rip and crack apart on me and I added in some tylose and it firmed it up. I was expecting it to harden like gumaspe but to my surprise it did not. I guess I only added enough to help hold it together and I got lucky. I have done black a few times and that was my only issue and that was with MMF. Since I switched to MFF I haven't had any issues at all. And honestly thinking back I used strawberry marshmellows that time because I needed the rest of the fondant to be a light pink color and I had issues with all of it. I think the type of marshmellows have an effect. I wish you luck.